Inflatable insulation for packaging

ABSTRACT

The invention disclosed herein relates to the use of dead air spaces to provide insulation for packaged materials. In one form of the invention, a nested pair of thermoplastic bags define an inflatable chamber therebetween, which chamber, upon being filled with air, provides a dead air space between the ambient atmosphere and the inner bag. The air space provides thermal insulation for the packaged material within the inner bag. In another form of the invention, a series of inflatable bi-walls, which are articulated to one another for subsequent formation into a rectangular parallelepiped shape, are disposed as a liner within a conventional corrugated paperboard container. When inflated, the bi-walls will insulate the packaged contents of the container. The bi-walls of the inflatable insulation used in either of the embodiments of the invention are fabricated from inexpensive, flexible but substantially non-elastic, thermoplastic film material which may be fabricated by conventional techniques and which may be readily heat sealed into any of the desired configurations.

United States Patent [191 Presnick INFLATABLE INSULATION FOR PACKAGING [76] Inventor: Michael C. Presnick, c/o

Metatronics Manufacturing Corp. 111 Bloomingdale Rd., Hicksville, NY. 11801 [22] Filed: Jan. 2, 1973 [21] App]; No.: 320,453

Related US. Application Data [62] Division of Ser. No. 124,717, March 16, 1971, Pat.

[52] US. Cl. 165/46; 206/522; 62/529 [51] Int. Cl. F28f 7/00 [58] Field of Search 165/46, 69, 47, 136; 62/529, 530; 206/522, DIG. 30; 126/263 [56] References Cited UNITED STATES PATENTS 3,552,466 l/l97l Fairchilds 206/DIG. 30

Primary ExaminerCharles Sukalo Attorney, Agent, or Firm-Mandevi1le and Schweitzer June 17, 1975 [5 7 ABSTRACT The invention disclosed herein relates to the use of dead air spaces to provide insulation for packaged materials. In one form of the invention, a nested pair of thermoplastic bags define an inflatable chamber therebetween, which chamber, upon being filled with air, provides a dead air space between the ambient atmosphere and the inner bag. The air space provides thermal insulation for the packaged material within the inner bag. In another form of the invention, a series of inflatable bi-walls, which are articulated to one another for subsequent formation into a rectangular parallelepiped shape, are disposed as a liner within a conventional corrugated paperboard container. When inflated, the bi-walls will insulate the packaged contents of the container. The bi-walls of the inflatable insulation used in either of the embodiments of the invention are fabricated from inexpensive, flexible but substantially non-elastic, thermoplastic film material which may be fabricated by conventional techniques and which may be readily heat sealed into any of the desired configurations.

2 Claims, 5 Drawing Figures PATENTEBJUN 17 I975 889,743

INFLATABLE INSULATION FOR PACKAGING This is a division of application Ser. No. 124,717, filed Mar. 16, 1971, now U.S. Pat. No. 3,730,240, granted May 1, 1973.

BACKGROUND OF THE INVENTION Inflatable, stretchable or elastic liners for packages have been known and employed in the packaging art for some time in expandable dunnage types of applications. Moreover, inflatable pneumatic structures of other types including furniture, boats, wastebaskets, tires, etc., have, of course, been long known to other of the industrial arts. The present invention represents an extension of these earlier teachings. More specifically, disclosed herein are two novel and practical inflatable structures which utilize to great advantage the extraordinary insulating characteristics of the dead air spaces contained in any inflated structure.

SUMMARY OF THE PRESENT INVENTION In one embodiment of the invention an inflatable thermos structure is fabricated from a pair of nested, flat folded envelopes, which are joined together at a common filling neck portion. A filling and dispensing spout of suitable construction is arranged at the neck of the structure to permit the material to be packaged to be inserted into the inner bag or envelope and to be subsequently removed therefrom. In accordance with the principles of the present invention, both the inner and outer bag and the filling and dispensing neck are made from readily available, inexpensive thermoplastic materials. Accordingly, the new insulated, inflatable container may be a disposable item which is designed for single usage.

A more rigid and stronger type of container may be constructed in accordance with the principles of the invention by lining a conventional parallelepiped, corruv gated container with a series of inflatable wall members, which members, when inflated, provide dead air spaces which completely envelop the central storage portions of the container. Heretofore, when it was desired to provide thermala insulation for cardboard or paperboard or corrugated containers, thermal was necessary to line them with layers of expanded polystyrene foam or comparable insulating materials. This type of construction has proved to be not only expensive, but it typically necessitates the forming and application of the inner insulating layers at the site of container manufacture. Accordingly, this type of insulated container is extremely space consuming, in terms of storage and shipping, before end use and is, therefore, extremely costly. In significant contrast, by employing inflatable walls in lieu of foam plastic walls or the like, it is possible to ship corrugated containers and deflated thermal insulation in a flat, knocked-down state to the end user, thereby saving significant amounts of space in both shipping and storage of insulated containers. As a more specific aspect of this embodiment of the invention, the inflatable wall members include straps for securing cylindrical chemical heating or cooling elements disposed at corners of the container.

Either embodiment of the invention may be rendered self-inflatable by the inclusion between the container walls of a small plastic cartridge containing a gas under pressure (i.e., a liquified gas), which container may be broken to liberate gas.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an inflated thermos-type bag embodying the principles of the invention;

FIG. 2 is a cross-section of the structure of FIG. 1 taken along line 22 thereof;

FIG. 3 is a plan view of an inflatable packaging liner;

FIG. 4 is a perspective view showing an inflated liner in place in a corrugated container in accordance with the principles of the present invention; and

FIG. 5 is a cross-sectional view of the structure of FIG. 4 taken through line 55 thereof.

DESCRIPTION OF THE INVENTION Referring now to FIG. 1, a thermos-type of flexible, collapsible, bag structure is disclosed therein. The new structure 10 comprises essentially an outer, substantially inelastic but flexible thermoplastic bag 11 and a nested, inner substantially inelastic but flexible thermoplastic bag 12. The two thermoplastic bags are maintained in a spacd relation to one another by the heat welding or other like attachment of the outer bag 11 to an elongated thermoplastic filling-dispensing tube 13 which projects from the upper edges of the inner bag 12. Thus, as shown in FIG. 1, the external wall surfaces of the inner bag 12 are substantially uniformly spaced from the internal wall surfaces of the outer bag 11, both of which bags are advantageously of plastic construction. The space between the walls of the inner and outer bags 11, 12 is designated by the reference numeral 14 and when inflated, represents a dead air space.

In accordance with the invention, both bags may be totally collapsed or flat folded for shipping and storage, in which case the space 14 is eliminated and the bag walls are in face-to-face, multilayered contact. Insulating air may be forced into the dead air space 14 through a thermoplastic inflation tube 15 formed along i the upper edge corner of the outer bag 11. The tubes 13 and 15 themselves may be collapsible and are in any event closed off to the atmosphere by appropriate stopper members 13', 15 as shown in FIG. 1. Alternatively, they may be otherwise sealed, e.g., by ultrasonic or heat welding transverse welds.

In accordance with the principles of the invention, the inner and outer bags 11 and 12 may be made of inexpensive thermoplastic sheet or film material and therefore, may be manufactured at low cost and in high volumes with simple, conventional techniques. Advantageously, to enhance the thermal insulating properties of the new thermos-type structure, the outer walls of the inner bag 12 and the inner walls of the outer bag 11 are provided with an appropriate reflective coating, i.e., a so-called silvered coating, by standard coating techniques, such as, for example, by vacuum deposition of aluminum.

As will be appreciated, the collapsible, thermos-type containers of the present invention may be shipped in a flat folded condition, and at the place and time of use, the inner bags may be filled through the filling tubes 13 with a commodity required to be maintained at a predetermined nonambient temperature while the deadair space 14 can be established by introducing air into the outer bags 11 through the tubes 15. Alternatively, and in lieu of inflation tube 15, a small plastic capsule or cartridge 20 containing an inflation medium 24 (a gas under pressure, e.g., a liquified gas), may be located between the walls 11, 12 for tacticle access from without the structure. The capsule for cartridge 20 may be rupturable or otherwise include a valve which is manipulatable from without the thermos structure to liberate an inflating gas from the capsule.

An alternate preferred embodiment of the invention is illustrated in FIGS. 3-5 and is an inflatable liner 40 used in conjunction with large, corrugated containers of the type heretofore lined with foamed-in-place expanded plastic for thermal insulating applications. In this embodiment, a thermoplastic liner made from appropriately shaped and heat-welded flexible but sub stantially inelastic thermoplastic sheets includes a plurality of interconnected bi-walled panels 41-48, each of which may be subsequently inflated when the liner 40 is inserted into a corrugated container or the like. More specifically, as shown in FIG. 3, the new liner includes consecutively articulated bi-walls 41-44 to biwalls 42 and 44 of which are articulated bi-walled endclosing flaps 45-48. As stated and shown best in FIG. 5, the panels 41-48 are bi-walled, that is, they comprise inner and outer walls joined at all but limited portions 57 of their perimeters 56. The portions 57 are interconnecting air passages. When the panels 41-48 are inflated, dead air spaces 50 (see FIG. are established therein. Inflation may be effected through an inflation tube 51 formed integrally with the blank 40 and through passages 57 or by use of self-inflation arrangements such as described hereinabove.

As an important specific aspect of the present invention, horizontal holding straps 55 are placed across at at least one and advantageously at two vertical lines of articulation 58 of the new liner 40, and are held in place by heat welds 59.

In use, the insulating liner 40 is inserted within a standard corrugated shipping container 60 and thereafter inflated through the tube 51 (or a capsule to create the dead air spaces 50 defined between the bi-walls of each of the panels 41-48 of the liner 40. The opposite inner walls of the liner 40 may be advantageously coated with a silvering material, such as vacuum deposited aluminum, to enhance the insulating properties of the inflated liner.

In accordance with the principles of the invention, a heat-transfer device 70, in the form of a sealed cylinder, may be inserted before inflation, between the bands 55 and the corners formed by the meeting of adjacent insulating walls of the liner 40 to provide a shipping container with both built-in insulation and builtin thermal properties. For example, the heat-transfer member may be comprised of a chemical compound commercially available as Transit Heat, a material designed to have predetermined thermal characteristics which are useful for heating and/or cooling pack aged goods. Advantageously, the cylinders 70 are held firmly between the pillow-like edges of adjacent biwalls and the straps 55.

As will be appreciated, the insulating liners 40 may be shipped in flat form to the site of package filling and carton erecting, and there, the liners may be inserted and inflated in place. This represents a departure from the previous practice of forming a rigid foamed insulating medium in place at the site of the carton manufacture. In accordance with the invention, it will now be possible for end users to form insulation in place only when actually needed and thus the new invention will enable insulating containers to be shipped andn stored economically in flat-folded collapsed condition.

I claim:

1. A rigid package comprising a. a rigid parallelepiped corrugated container having six planar walls;

b. a substantially inelastic liner means of thermoplastic material including a plurality of articulated inflatable insulating chambers;

c. each of said insulating chambers comprising spaced inner and outer walls joined at their edges by elongated heat seals, at least one of which seals is discontinuous for the communication of air between adjacent chambers;

d. valve means disposed in one chamber for the admission of air to all of said chambers;

e. said chambers when inflated being adapted to provide a closed, insulated storage space within the central portions of said paperboard container;

f. a heat exchange means; and

g. means supporting said heat exchange means against said liner means.

2. The package of claim 1, in which a. thermoplastic holding straps are disposed at joints between pairs of said chambers to hold said heat exchange means in place within said package. 1: 

1. A rigid package comprising a. a rigid parallelepiped corrugated containEr having six planar walls; b. a substantially inelastic liner means of thermoplastic material including a plurality of articulated inflatable insulating chambers; c. each of said insulating chambers comprising spaced inner and outer walls joined at their edges by elongated heat seals, at least one of which seals is discontinuous for the communication of air between adjacent chambers; d. valve means disposed in one chamber for the admission of air to all of said chambers; e. said chambers when inflated being adapted to provide a closed, insulated storage space within the central portions of said paperboard container; f. a heat exchange means; and g. means supporting said heat exchange means against said liner means.
 2. The package of claim 1, in which a. thermoplastic holding straps are disposed at joints between pairs of said chambers to hold said heat exchange means in place within said package. 